Structural dynamics of SARS-CoV-2 nucleocapsid protein induced by RNA binding.

The nucleocapsid (N) protein of the SARS-CoV-2 virus, the causal agent of COVID-19, is a multifunction phosphoprotein that plays critical roles in the virus life cycle, including transcription and packaging of the viral RNA. To play such diverse roles, the N protein has two globular RNA-binding modules, the N- (NTD) and C-terminal (CTD) domains, which are connected by an intrinsically disordered region. Despite the wealth of structural data available for the isolated NTD and CTD, how these domains are arranged in the full-length protein and how the oligomerization of N influences its RNA-binding activity remains largely unclear. Herein, using experimental data from electron microscopy and biochemical/biophysical techniques combined with molecular modeling and molecular dynamics simulations, we show that, in the absence of RNA, the N protein formed structurally dynamic dimers, with the NTD and CTD arranged in extended conformations. However, in the presence of RNA, the N protein assumed a more compact conformation where the NTD and CTD are packed together. We also provided an octameric model for the full-length N bound to RNA that is consistent with electron microscopy images of the N protein in the presence of RNA. Together, our results shed new light on the dynamics and higher-order oligomeric structure of this versatile protein.

Carvacrol reduces blood pressure, arterial responsiveness and increases expression of MAS receptors in spontaneously hypertensive rats.

AIM: To analyze the effect of the use of carvacrol in the cardiovascular system of spontaneously hypertensive rats (SHR). METHODS: Methods: Twenty animals were allocated in four groups, one group control Wistar receiving only sorbitol, used as vehicle of administration of the carvacrol (Wistar-Vehicle), one control group SHR, also receive only sorbitol (SHR-Vehicle), a third, treated with losartan (SHR-Losartan/50 mg/kg), and the fourth, treated with carvacrol (SHR - Carvacrol/20 mg/kg). Sorbitol, losartan and carvacrol were administered by oral gavage daily for 30-day. Hemodynamic variables, vascular reactivity, biochemical parameters, and expression of Mas and AT1 receptors in kidney tissues were analyzed. RESULTS: SHR- Carvacrol group showed a maximal effect of inhibition of 56% in the curve of norepinephrine. The Emax of the curves with Ca2+ were smaller in the groups SHR-losartan (40.17%) and SHR-carvacrol (35.71%) when compared to the SHR-Vehicle. The carvacrol increased the expression of the MAS receptors in kidney tissue. CONCLUSION: Thirty days of treatment with carvacrol showed an antihypertensive effect associated with less peripheral vascular resistance. Also, treatment with carvacrol increased the expression of MAS receptors in kidney tissue.

Effect of treatment with carvacrol and aerobic training on cardiovascular function in spontaneously hypertensive rats.

NEW FINDINGS: What is the central question of this study? Can two non-drug therapies, carvacrol and aerobic physical training, together have additive effects on the reduction of cardiovascular risks and control of arterial hypertension? What is the main finding and its importance? The oral use of carvacrol (20 mg/kg/day) can control sustained hypertension in spontaneously hypertensive rats, and when this use is associated with aerobic physical training, there is a more pronounced effect on the reduction of blood pressure values, making these therapies an adjunct option in the drug treatment of hypertension. ABSTRACT: Systemic arterial hypertension is considered the foremost cardiovascular risk factor, and it is important to examine different therapies that help prevent and treat it, especially when associated with other cardiovascular risk factors. In this context, it is known that both carvacrol and aerobic physical training benefit the cardiovascular system. This study investigated the effects of treatment with carvacrol combined with aerobic exercise on hypertensive rats with cardiovascular risk parameters. We used an experimental design with six groups: normotensive control (Wistar rats); hypertensive control (spontaneously hypertensive rats, SHR); positive control rats treated with amlodipine (Aml-20 mg); rats treated with carvacrol (Carv-20 mg); rats trained with exercise (Exer); and rats treated with carvacrol and exercise (ExerCarv). The treatment lasted for 4 weeks, monitoring heart rate and systolic blood pressure (SBP). At the end of the treatment, vascular reactivity tests were performed in addition to biochemical measurements of urea, creatinine, aspartate aminotransferase, alanine aminotransferase, triglycerides, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, atherogenic indexes, relative heart weight and histopathological analysis of cardiac perivascular tissue. Significant reductions in SBP were observed after the training period, with the ExerCarv group showing a greater magnitude of reduction (∆SBP = 88 ± 10.0 mmHg, 42%). This group also experienced reductions in atherogenic indices and improvement in all analysed lipid parameters, with no differences observed in the Exer group. The findings indicated that the interaction between aerobic exercise and carvacrol offers a greater BP reduction. Exercise is particularly effective for controlling biochemical parameters of cardiovascular risk, regardless of carvacrol use.

Clinical and Radiographic Evaluation of Patients Operated by the Bristow-Latarjet Technique with a Minimum Follow-Up of 20 Years.

Objective To verify the results of 27 patients submitted to surgery from 1990 to 1997 by the Bristow-Latarjet technique for the treatment of anterior traumatic instability of the shoulder. The analysis included the possible complications, especially the appearance of arthropathy. Methods The subjective clinical evaluation was performed through a questionnaire answered by the patients, and the objective evaluation was performed using the Rowe et al score. The radiographic evaluation was performed using the anteroposterior (true) incidence to detect signs of shoulder arthrosis, according to the classification of Samilson and Prieto, as well as the apical oblique and the Bernageau and Patte incidences to verify the consolidation of the bone graft, the position of the screw and of the graft, and signs of the release of the synthesis material. These evaluations were performed by two examiners at different times without interference between them. Results In the subjective assessment of the patients, 93% were fully recovered, and, in the objective evaluation, the average was 95 points on the Rowe et al score. Complications related to coracoid placement were not found. The degree of arthropathy of the shoulders, according to the Samilson and Prieto classification, presented an average of seven mild cases, two moderate cases and one severe case. In total, 17 patients did not present arthropathy. Conclusion Between the first and second evaluations, there was no change in the efficacy of the Bristow-Latarjet technique. The careful observation of the criteria of the technique was fundamental to avoid complications. The occurrence of arthropathy in the long term was not relevant in our evaluation. Based on the evidences of the present study, the surgical procedure alone is not the cause of the onset of the arthropathy, but the failure in its execution.

Clinical and Radiographic Evaluation of Patients Operated by the Bristow-Latarjet Technique with a Minimum Follow-Up of 20 Years / Avaliação clínica e radiográfica de pacientes operados pela técnica de Bristow-Latarjet com seguimento mínimo de 20 anos

Abstract Objective To verify the results of 27 patients submitted to surgery from 1990 to 1997 by the Bristow-Latarjet technique for the treatment of anterior traumatic instability of the shoulder. The analysis included the possible complications, especially the appearance of arthropathy. Methods The subjective clinical evaluation was performed through a questionnaire answered by the patients, and the objective evaluation was performed using the Rowe et al score. The radiographic evaluation was performed using the anteroposterior (true) incidence to detect signs of shoulder arthrosis, according to the classification of Samilson and Prieto, as well as the apical oblique and the Bernageau and Patte incidences to verify the consolidation of the bone graft, the position of the screw and of the graft, and signs of the release of the synthesis material. These evaluations were performed by two examiners at different times without interference between them. Results In the subjective assessment of the patients, 93% were fully recovered, and, in the objective evaluation, the average was 95 points on the Rowe et al score. Complications related to coracoid placement were not found. The degree of arthropathy of the shoulders, according to the Samilson and Prieto classification, presented an average of seven mild cases, two moderate cases and one severe case. In total, 17 patients did not present arthropathy. Conclusion Between the first and second evaluations, there was no change in the efficacy of the Bristow-Latarjet technique. The careful observation of the criteria of the technique was fundamental to avoid complications. The occurrence of arthropathy in the long term was not relevant in our evaluation. Based on the evidences of the present study, the surgical procedure alone is not the cause of the onset of the arthropathy, but the failure in its execution.

Resumo Objetivo Verificar os resultados do procedimento cirúrgico de 27 pacientes operados, durante o período de 1990 a 1997, pela técnica de Bristow-Latarjet para tratamento da instabilidade traumática anterior do ombro, considerando as possíveis complicações, e, principalmente, o aparecimento de artropatia. Métodos A avaliação clínica subjetiva foi realizada por meio de um questionário respondido pelos pacientes, e a avaliação objetiva foi feita mediante o escore de Rowe et al. A avaliação radiográfica foi realizada usando as incidências anterioposterior (verdadeira), para visualizar a presença de sinais de artrose do ombro, segundo a classificação de Samilson e Prieto, e oblíqua apical e de Bernageau e Patte, para verificar a consolidação do enxerto ósseo, o posicionamento do parafuso, do enxerto, e os sinais de soltura do material de síntese. Estas avaliações foram realizadas por dois examinadores em tempos diferentes, sem interferência entre eles. Resultados Na avaliação subjetiva dos pacientes, 93% estavam totalmente recuperados, e, na avaliação objetiva, a média foi de 95 pontos na escala de Rowe et al. Não foram encontradas as complicações relativas à colocação do enxerto de coracoide. O grau de artropatia dos ombros, de acordo com a classificação de Samilson e Prieto, apresentou uma média de sete casos suaves, dois casos moderados, e um caso grave. No total, 17 pacientes não apresentaram artropatia. Conclusão Entre a primeira e a segunda avaliações, não houve alteração quanto à eficácia da técnica de Bristow-Latarjet. A observação cuidadosa dos critérios da técnica foi fundamental para evitar complicações. A ocorrência de artropatia em longo prazo não foi relevante em nossa avaliação. Pelas evidências do presente estudo, somente o procedimento cirúrgico não é a causa do surgimento da artropatia, mas a falha na sua execução.

Essential oils as molluscicidal agents against schistosomiasis transmitting snails - a review.

This review aims to describe essential oils with bioactivity on adult snails of the genera Bulinus and Biomphalaria, which are intermediate hosts of schistosomes, and brings together information relating to the importance of molluscicides and the chemical composition and toxicity of such oils for other aquatic species. Analysis of the data of original articles revealed that 50 essential oils obtained from 46 plant species were evaluated for molluscicidal activity against the genera cited. More than 80% of the volatile oils studied were active, according to the criteria of the World Health Organization (LC90 or LC100 ≤100 µg/mL or LC50 <40 µg/mL), and most of the oils came from plants belonging to the Rutaceae, Lamiaceae and Pinaceae. Around 37% of the surveyed plant species were obtained in Brazil and 88% of these plants were collected in the northeast of the country, a region with a high prevalence of schistosomiasis mansoni. The essential oils with the highest toxicity against host snails had high levels of hydrocarbon monoterpenes and oxygenated monoterpenes, which may be responsible for the molluscicidal activity. Some volatile components were subjected to molluscicidal evaluation, and the monoterpene compounds exhibited a significant molluscicide effect. This review confirmed the importance of essential oils as a promising alternative for the development of natural molluscicide products. However, in order to be safe for use at sites where schistosome intermediate hosts are found, information on ecotoxicity is required and, to date, few oils have been tested against non-target aquatic species.

Hydroalcoholic extract of leaves of Arrabidaea brachypoda (DC. ) Bureau present antispasmodic activity mediated through calcium influx blockage

Aim: Since other species of the Bignoniaceae Family presented of antispasmodic activity, it was decided, by chemotaxonomic criterion, to determine the antispasmodic activity of the leaves of Arrabidaea brachypoda. Methodology: the segments of the rat jejunum were suspended in glass vats containing specific saline solution, at an appropriate temperature, and after stabilization period, were stimulated by a contractile agent to observe the inhibitory or relaxing effect of EH-FAB. Results: EH-FAB showed the presence of 10 compounds, mainly rutin and it has an antispasmodic activity as it inhibits the phasic component and relaxes the tonic component of the contraction in isolated rat jejunum. To assess the mechanism of antispasmodic action, cumulative curves to the CCh were performed in which a non-competitive antagonism was observed, due to a displacement of the control curve to the right and reduction of the maximum contraction effect (Emax). Afterward, the participation of the calcium and/or potassium channels was evaluated by increasing the extracellular potassium, and it was observed that the EH-FAB relaxed the rat jejunum, suggesting the participation of the Ca2+ channels. To corroborate that hypothesis, the EH-FAB was tested against cumulative curves to Ca2+ in a free depolarizing solution of Ca2+, and it was observed that there was a shift of the curve to the right with a reduction in Emax. Conclusions: EH-FAB presents antispasmodic activity in isolated rat jejunum and it is suggested to block the influx of Ca2+ through voltage-gated calcium channels, signaling the therapeutic potential for the treatment of colic and/or diarrhea.(AU)

From Inflammation to Current and Alternative Therapies Involved in Wound Healing.

Wound healing is a complex event that develops in three overlapping phases: inflammatory, proliferative, and remodeling. These phases are distinct in function and histological characteristics. However, they depend on the interaction of cytokines, growth factors, chemokines, and chemical mediators from cells to perform regulatory events. In this article, we will review the pathway in the skin healing cascade, relating the major chemical inflammatory mediators, cellular and molecular, as well as demonstrating the local and systemic factors that interfere in healing and disorders associated with tissue repair deficiency. Finally, we will discuss the current therapeutic interventions in the wounds treatment, and the alternative therapies used as promising results in the development of new products with healing potential.

Molecular studies with Aedes (Stegomyia) aegypti (Linnaeus, 1762), mosquito transmitting the dengue virus.

Dengue is an infectious viral disease, which can present a wide clinical picture, ranging from oligo or asymptomatic forms, to bleeding and shock, and can progress to death. The disease problem has increased in recent years, especially in urban and suburban areas of tropical and subtropical regions. There are five dengue viruses, called serotypes (DEN-1, DEN-2, DEN-3, DEN-4, and DEN-5), which belong to the Flaviviridae family and are transmitted to humans through infected mosquito bites, with the main vector the Aedes aegypti mosquito (Linnaeus, 1762). Studies performed with Ae. aegypti, aimed at their identification and analysis of their population structure, are fundamental to improve understanding of the epidemiology of dengue, as well for the definition of strategic actions that reduce the transmission of this disease. Therefore, considering the importance of such research to the development of programs to combat dengue, the present review considers the techniques used for the molecular identification, and evaluation of the genetic variability of Ae. aegypti.

Antinociceptive and Anti-inflammatory Effects of Triterpenes from Pluchea quitoc DC. Aerial Parts.

BACKGROUND: Pluchea quitoc DC. (Asteraceae), a medicinal plant known as "quitoco," "caculucage," "tabacarana" and "madre-cravo," is indicated for inflammatory conditions such as bronchitis, arthritis, and inflammation in the uterus and digestive system. OBJECTIVE: This study evaluated the analgesic and anti-inflammatory activities of the triterpenes compounds obtained from P. quitoc aerial parts. MATERIALS AND METHODS: The triterpenes compounds ß-amyrin, taraxasterol and pseudo-taraxasterol in a mixture (T); ß-amyrin, taraxasterol and pseudo-taraxasterol acetates in a mixture (Ta); ß-amyrin, taraxasterol, pseudo-taraxasterol acetates in a mixture with ß-amyrin, taraxasterol and pseudo-taraxasterol myristates (Tafe) were analyzed in the models of nociception and inflammation. The evaluation of antinociceptive activity was carried out by the acetic acid-induced writhing and tail-flick tests while leukocyte migration to the peritoneal cavity was used for anti-inflammatory profile. RESULTS: The oral administration of T or Tafe (40 mg/kg and 70 mg/kg) and Ta (70 mg/kg) to mice reduced acetic acid-induced writhing. The tail-flick response of mice was not affected by T or Tafe (40 mg/kg). T or Tafe (40 mg/kg) and Ta (70 mg/kg) also inhibited peritoneal leukocyte infiltration following the injection of carrageenan. CONCLUSION: The results demonstrate the anti-inflammatory and peripheral antinociceptive activity of the triterpenes ß-amyrin, taraxasterol, and pseudo-taraxasterol that were decreased when these were acetylated; while the acetylated triterpenes in mixture with myristyloxy triterpenes improved this activity. These compounds seem, at least in part, to be related to the plant's reported activity. SUMMARY: The mixtures of hydroxylated, acetylated, and myristate triterpenes isolated from hexanic extracts of Pluchea quitoc DC. were analyzed in the models of nociception and inflammation in mice. The results demonstrate the anti-inflammatory and peripheral antinociceptive activity of the triterpenes ß-amyrin, taraxasterol, and pseudo-taraxasterol. This study showed too that the activity of triterpenes may be decreased by their being acetylated, while the acetylated triterpenes in mixture with myristate triterpenes improved this activity.Abbreviations Used: T: Triterpenes compounds ß-amyrin, taraxasterol, and pseudo-taraxasterol in a mixture, Ta: Triterpenes compounds ß-amyrin, taraxasterol and pseudo-taraxasterol acetates in a mixture, Tafe: Triterpenes compounds ß-amyrin, taraxasterol, pseudo-taraxasterol acetates in a mixture with ß-amyrin, taraxasterol and pseudo-taraxasterol myristates, Ctrl: Control, Indo: Indomethacin, Dexa: Dexamethasone, EtOAc: Ethyl acetate, MeOH: Methanol.

Mast Cell Proteases 6 and 7 Stimulate Angiogenesis by Inducing Endothelial Cells to Release Angiogenic Factors.

Mast cell proteases are thought to be involved with tumor progression and neo-vascularization. However, their exact role is still unclear. The present study was undertaken to further elucidate the function of specific subtypes of recombinant mouse mast cell proteases (rmMCP-6 and 7) in neo-vascularization. SVEC4-10 cells were cultured on Geltrex® with either rmMCP-6 or 7 and tube formation was analyzed by fluorescence microscopy and scanning electron microscopy. Additionally, the capacity of these proteases to induce the release of angiogenic factors and pro and anti-angiogenic proteins was analyzed. Both rmMCP-6 and 7 were able to stimulate tube formation. Scanning electron microscopy showed that incubation with the proteases induced SVEC4-10 cells to invade the gel matrix. However, the expression and activity of metalloproteases were not altered by incubation with the mast cell proteases. Furthermore, rmMCP-6 and rmMCP-7 were able to induce the differential release of angiogenic factors from the SVEC4-10 cells. rmMCP-7 was more efficient in stimulating tube formation and release of angiogenic factors than rmMCP-6. These results suggest that the subtypes of proteases released by mast cells may influence endothelial cells during in vivo neo-vascularization.

Antihypertensive Effect of Syzygium cumini in Spontaneously Hypertensive Rats.

This study evaluated the in vivo potential antihypertensive effect of hydroalcoholic extract of Syzygium cumini leaves (HESC) in normotensive Wistar rats and in spontaneously hypertensive rats (SHR), as well as its in vitro effect on the vascular reactivity of resistance arteries. The hypotensive effect caused by intravenous infusion of HESC (0.01-4.0 mg/kg) in anesthetized Wistar rats was dose-dependent and was partially inhibited by pretreatment with atropine sulfate. SHR received HESC (0.5 g/kg/day), orally, for 8 weeks and mean arterial pressure, heart rate, and vascular reactivity were evaluated. Daily oral administration of HESC resulted in a time-dependent blood pressure reduction in SHR, with a maximum reduction of 62%. In the endothelium-deprived superior mesenteric arteries rings the treatment with HESC reduced by 40% the maximum effect (E max⁡) of contraction induced by NE. The contractile response to calcium and NE of endothelium-deprived mesenteric rings isolated from untreated SHR was reduced in a concentration-dependent manner by HESC (0.1, 0.25, and 0.5 mg/mL). This study demonstrated that Syzygium cumini reduces the blood pressure and heart rate of SHR and that this antihypertensive effect is probably due to the inhibition of arterial tone and extracellular calcium influx.

The toxicity evaluation of Syzygium cumini leaves in rodents

This study aimed to evaluate the safety of the hydroalcoholic extract (HE) of Syzygium cumini (L.) Skeels, Myrtaceae, leaves in rodents. Acute toxicity was evaluated through the determination of a LD50 in mice and rats (up to 14 days). In mice, the oral administration (p.o.) of the HE (0.1 at 6 g/kg) did not cause any death. When administered by intraperitoneal route (i.p.) the HE (0.1 at 1 g/kg) caused death of the animals (LD50 of 0.489 g/kg). In rats, the HE (0.5, 1 and 2 g/kg, p.o.) did not cause any death, while by i.p., only the 2 g/kg dose was lethal to 67 percent of the animals. To evaluate chronic toxicity, groups of rats daily received the HE (0.05, 0.1 and 0.25 g/kg) through p.o., during 30, 90 or 180 days and the effects on behavior, body weight, feed consumed were measured. Histology, hematology and biochemical parameters were measured at the end of the treatment. After a 30-day treatment, the HE caused changes in some biochemical parameters. Histological examination of the liver, kidneys, lungs, heart, stomach, intestine and pancreas showed normal architecture suggesting no morphological disturbances. These data may mean that the HE of S. cumini does not exert acute or chronic toxic effects by oral administration.

Fratura epifisiolise da extremidade proximal do úmero com luxação intratorácica: relato de caso / Epiphysiolysis fracture of the proximal end of the humerus with intrathoracic dislocation: a case report

A fratura da extremidade proximal do úmero com luxação intratorácica foi relatada em 1949 por West, em que a fratura era, somente, do tubérculo maior. Desde então, poucos casos foram relatados na literatura, a maioria constituída por pessoas idosas, prevalecendo como indicação terapêutica artroplastia parcial. Os autores relatam o caso de um adolescente de 14 anos de idade, sexo masculino, que apresentou fratura epifisiolise da extremidade proximal do úmero com luxação intratorácica em decorrência de acidente ciclístico e que foi submetido a tratamento cirúrgico com redução, osteossíntese e reinserção do manguito rotador. A recuperação da cabeça do úmero totalmente desvitalizada e o acompanhamento do processo de necrose e revas cularização durante seis anos, em paciente adolescente, parece não terem sido previamente relatados.

Fracture of the proximal end of the humerus with intrathoracic dislocation was reported in 1949 by West, and the fracture was only a fracture of the greater tubercle. Few cases have since been published, and most of them in elderly individuals, partial arthroplasty prevailing as the therapy indication. The authors report the case of a 14 year old boy who presented with an epiphysiolysis fracture of the proximal end of the humerus with intrathoracic dislocation resulting from a bicycle accident. The boy was submitted to surgical treatment with reduction, osteosynthesis, and reinsertion of the rotator cuff. The totally devitalized humeral head recovery and the monitoring of the necrosis and revascularization process for a period of six years in a teenager patient seems to have never been reported before.

Efeito da ropivacaína na recaptação neuronal de noradrenalina em músculo liso / Effect of ropivacaine on neuronal norepinephrine reuptake in smooth muscle

JUSTIFICATIVA E OBJETIVOS: Além da ação anestésica local, a ropivacaína apresenta efeito vasoconstritor, clinicamente significativo, que pode ser observado quando da anestesia infiltrativa, o que a torna um anestésico importante no bloqueio de campo. Este trabalho teve por objetivo caracterizar o mecanismo de ação constritora da ropivacaína em músculo liso. MÉTODO: Em preparações isoladas de ducto deferente de ratos foram construídas curvas concentração-efeito de noradrenalina na ausência ou na presença da ropivacaína. Em outra série de experimentos os ratos foram tratados com reserpina (10 mg.kg-1, por via intraperitoneal) para avaliar a reatividade dos ductos deferentes à tiramina ou noradrenalina, na ausência ou presença da ropivacaína. RESULTADOS: A ropivacaína nas concentrações de 5 ou 10 æg.mL-1 potencializou o efeito máximo (Emax) da noradrenalina em 47 por cento e 35 por cento, respectivamente, enquanto que nas concentrações de 50 ou 100 æg.mL-1 inibiu o efeito máximo produzido por este agonista. Em ductos deferentes isolados de ratos reserpinizados, a ropivacaína (10 ou 20 æg.mL-1) potencializou (150 por cento e 25 por cento, respectivamente) as contrações induzidas pela noradrenalina, enquanto que as concentrações de 50 ou 100 æg.mL-1 não alteraram as respostas à noradrenalina. CONCLUSÕES: Os resultados obtidos permitem concluir que a ropivacaína bloqueia a recaptação neuronal de noradrenalina pelos terminais nervosos simpáticos.

[Effect of ropivacaine on neuronal norepinephrine reuptake in smooth muscle.]. / Efeito da ropivacaína na recaptação neuronal de noradrenalina em músculo liso.

BACKGROUND AND OBJECTIVES: In addition to local anesthetic action, ropivacaine has clinically significant vasoconstrictor effects, which may be observed at infiltrative anesthesia, making it an important anesthetic for field blockade. This study aimed at characterizing the constrictor mechanism of ropivacaine on smooth muscles. METHODS: Norepinephrine concentration-effect curves in the absence or presence of ropivacaine were plotted on isolated preparations of vas deferens of rats. In another series of experiments rats were treated with reserpine (10 mg.kg-1, i.p.) to evaluate vas deferens reactivity to tyramine or norepinephrine, in the absence or presence of ropivacaine. RESULTS: Ropivacaine 5 or 10 microg.mL-1 potentiated maximum norepinephrine effect (Emax) in 47% and 35%, respectively, while higher concentrations (50 or 100 microg.mL-1) inhibited its maximum effect. In isolated vas deferens of rats treated with reserpine, ropivacaine (10 or 20 microg.mL-1) potentiated (150% and 25%, respectively) norepinephrine-induced contractions, while higher concentrations (50 or 100 microg.mL-1) have not changed responses to norepinephrine. CONCLUSIONS: Ropivacaine blocks neuronal norepinephrine reuptake by sympathetic nerve terminals.

Efeitos da administraçäo de colecalciferol sobre as respostas vasculares de ratos espontaneamente hipertensos / Effect of colecalciferol administration on vascular responses from spontaneously hypertensive rats

O mecanismo responsável pela redução da pressão arterial em ratos espontaneamente hipertensos (SHR), após o tratamento crônico com colecalciferol foi estudado. Após 2 semanas de tratamento dos SHR com O,125 mg de colecalciferol por kg de peso por via oral observou-se significante redução da pressão arterial sistólica e da pressão basal de perfusão do leito vascular mesentérico sob fluxo constante. Este tratamento também reduziu o efeito máximo da resposta induzida pela adrenalina, provavelmente devido à recuperação de canais de K+ dependentes de Ca 2+ acoplados aos adrenoceptores a2.Este tratamento também normalizou o potencial de membrana das células de músculo liso das artérias mesentéricas sem endotélio, bem como as respostas hiperpolarizantes induzidas por agonistas (a2, as quais estão inibidas em SHR não tratados. Em anéis mesentéricos com endotéiio os agonistas de adrenoceptores a2 causam respostas hiperpolarizantes similares em SHR, em ratos normotensos Wistar (NWR) e nos ratos Wistar Kyoto (WKY). Antes do tratamento de SHR com colecalciferol, o mediador da resposta hiperpolarizante foi o óxido nítrico (NO), enquanto que nos normotensos foi o fator hiperpolarizante endotelial (EDHF). Após o tratamento a resposta hiperpoiarizante induzida pelos agonistas a2 foi mediada pelo EDHF em ambas as cepas. Nossos resultados indicam que o efeito hipotensor do colecalciferol em SHR é provavelmente devido à normalização do funcionamento dos canais de K+ dependentes de Ca 2+ e/ou ATP localizados na membrana das células de músculo liso vascular, que estavam inoperantes. O efeito deste tratamento foi também estudado sobre as respostas relaxantes e hiperpolarizantes dependentes do endotélio à acetilcolina (ACh) e à bradicinina (BK) em anéis e leito vascular mesentéricos, as quais se encontram reduzidas em SHR quando comparadas aos seus controles normotensos. Após o tratamento com colecalciferol estas respostas foram normalizadas. As respostas à ACh foram inibidas pelo L-NNA em SHR e pela apamina nos WKY. Após o tratamento, as respostas hiperpolarizantes à ACh em SHR mostraram o mesmo padrão de inibição dos ratos normotensos. Isso indica que as respostas à ACh nas preparações vasculares mesentéricas de SHR são mediadas pelo EDRF e após o tratamento passaram a ser mediadas pelo EDHF, como ocorre nos ratos normotensos

Instabilidade anterior do ombro: tratamento cirúrgico pela técnica de Bristow-Latarjet / Anterior instability of the shoulder: surgical treatment by Bristow-Latarjet technique

Os autores mostram neste trabalho o resultado cirúrgico de 56 pacientes com instabilidade anterior traumática do ombro submetidos à técnica de Bristow-Latarjet. Foi realizada análise retrospectiva de sete anos, que objetivou a observação das complicações do referido método descritas na literatura, o resultado funcional obtido e o grau de satisfação dos pacientes. Foi constatada discreta limitação da rotação externa do ombro em 11 pacientes (19,6 por cento dos casos) e recuo do parafuso em 1 (0,5 por cento), mas sem prejuizo funcional. Quanto às outras complicações, citadas por alguns autores, não foram observadas, podendo-se dizer que, no presente trabalho, todos os pacientes se mostraram satisfeitos com o resultado do tratamento.

Insuficiência renal aguda na rabdomiólise alcoólica / Acute kidney failure in alcoholic rhabdomyolysis

Intoxicaçäo aguda por etanol pode causar rabdomiólise e mioglobulinúria. Apresentamos sete casos de pacientes alcoólatras que desenvolveram insuficiência renal aguda em conseqüência de rabdomiólise. O critério para diagnóstico de rabdomiólise foi elevaçäo de cinco vezes nos níveis de CPK sérico, na ausência de lesäo cardíaca ou cerebral. Todos os pacientes tinham história de alcoolismo e näo apresentavam trauma, doenças infecciosas ou uso de drogas. Cinco pacientes apresentaram convulsöes ou delirium tremens precedendo o quadro de insuficiência renal. Apenas dois pacientes apresentavam sinais e sintomas de lesäo muscular. Os achados laboratoriais iniciais em nossos pacientes foram: CPK sérico 3.709 ñ 6.23IU/L, potássio 4,8 ñ 0,9mEq/1, cálcio 8,9 ñ 0,9mg%, fósforo 4,6 ñ 0,9%. Em todos os pacientes a creatinina sérica chegou a níveis superiores a 9mg%. Em seis pacientes, foi realizado exame de urina tipo I, que mostrou alteraçäo em todos os casos (hematúria, leucocitúria ou proteinúria). Em cinco pacientes, havia pigmentúria detectável. Seis pacientes foram submetidos a tratamento dialítico. Seis pacientes recuperaram a funçäo renal e um paciente faleceu por sepse. Insuficiência renal aguda devida a rabdomiólise näo traumática tem que ser considerada no diagnóstico diferencial de IRA, particularmente em pacientes alcoólatras. Raramente é precedida de sinais de doença muscular e alteraçöes no sedimento urinário säo comuns. A determinaçäo de CPK sérico é fundamental no diagnóstico dessa condiçäo